How to extend class with implicit parameter in Scala

Question

class B(implicit imp: Int) extends AC { }

object C extends B{

}

Error: could not find implicit value for parameter imp

This is what i was looking for: How to provide default value for implicit parameters at class level

Since object does not have a constructor it cannot be done. But you can have a class extending the other class `class B(implicit imp: Int) extends A(imp)` — Eugene Ryzhikov, Mar 17 '14 at 21:05

score 5 · Answer 1 · answered Mar 17 '14 at 21:19

5

You extend it like you extend a class with non-implicit parameters, but you need an empty parameter list first:

scala> object C extends B()(5) {}
defined module C

answered Mar 17 '14 at 21:19

Daniel C. Sobral

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score 1 · Accepted Answer · answered Mar 17 '14 at 21:31

1

scala> class B(implicit imp:Int)
defined class B

scala> class C extends B()(1)
defined class C

scala> implicit val imp:Int = 2
imp: Int = 2

scala> class D extends B
defined class D

scala>

answered Mar 17 '14 at 21:31

nairbv

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How to extend class with implicit parameter in Scala

2 Answers2